Cypress VS Storybook for Component Testing Vue

In this post, I'm going to break down using Cypress and Storybook to test your components. They are both great tools, but offer slightly different experiences (and end results). Choosing which tool comes down to your end goal.

Here are a few questions to ask yourself:

• Why are you implementing a component testing tool?
• Do you use either tool already?
• What will the learning curve be for your dev team?

We currently use Cypress for our e2e testing, and Storybook to house our UX design library and documentation. We wanted to carefully evaluate both options, as well as our motivations to pick the best tool.

TLDR - If your team uses Cypress already and your goal is to minimize the learning curve, use Cypress. It's a great tool, and will allow you to start writing component tests quickly. If your goal is to build a robust and well-maintained Storybook library (or test speed is a concern) then choose Storybook.

Maybe Neither?

Our primary motivation was to find a reliable and robust component testing tool. The component testing landscape can be overwhelming. When looking at example code for many component tests it feels like it will be quite cumbersome to write simple, clean tests.

I don't know about you, but I hate wasting time on tests that are brittle and hard to maintain.

We first took a look at Vue Testing Library. Vue recommends that you keep your tests high level and don't try to test implementation details. With this in mind, I feel a non-visual testing tool makes it a lot harder to write good tests. If you can't see what the component is doing, it seems a lot harder to debug. We decided to pass and look at Cypress VS Storybook.

Let's dig in!

Cypress Component Testing

Pros

• Less to Learn: If you're already using Cypress for e2e testing, the learning curve is minimal
• Shared Code: You can share custom commands and utilities across your e2e and component tests
• Recommended by Vue: The Vue core team recommends Cypress for component testing
• Mature Solution: Cypress has been around longer and has more established patterns

Cons

• Slower: Cypress component tests are slower than Storybook's Playwright-based tests
• Separate Files: You need to maintain both component tests and stories separately
• Command Queuing: The Cypress command queuing syntax can be more complex than async/await

Storybook Component Testing

Pros

• Encourages Component Library: Forces you to maintain a robust component library
• Faster Testing: Uses Playwright under the hood, which is faster than Cypress
• Cleaner Syntax: Modern async/await syntax is easier to read and write
• Integrated: Tests live alongside your component stories

Cons

• Newer Approach: Less established, fewer patterns and examples
• Learning Curve: New syntax to learn if you're not familiar with Storybook
• CI Configuration: Can be more challenging to configure in CI/CD pipelines
• Mocking: Harder to mock and stub API calls compared to Cypress

The Verdict

You really can't go wrong with either one!

The choice ultimately depends on your team's context:

• Choose Cypress if: You're already using it for e2e tests and want to minimize the learning curve
• Choose Storybook if: You want to build a robust component library and test speed is important
• Consider Playwright: If you're starting fresh and want cross-browser testing capabilities

Both tools will help you write better component tests and improve your application's quality. The best choice is the one that fits your team's existing workflow and goals.

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Originally published on October 6, 2022